Level:
Project ID:
1003029706
Accepted:
1
Clonable:
0
Easy:
0
In a river, water flows at speed of \( 1\,\mathrm{mps} \). A boat, which moves at speed of \( 4\,\mathrm{mps} \) in a calm water, carries mail to a little town distant \( 6\,\mathrm{km} \) downstream. How long will it take till the boat returns? (We disregard the time necessary for mail-handover.) Note: Abbreviation "mps" stands for meter per second.
\( 53\,\mathrm{min}\ 20\,\mathrm{s} \)
\( 50\,\mathrm{min} \)
\( 3\,\mathrm{min}\ 12\,\mathrm{s} \)
\( 1\,\mathrm{min}\ 20\,\mathrm{s} \)